Subject: Re: [PATCH 05/15] powerpc/powernv: Split out set MSI IRQ chip code

From: Gavin Shan <[email-masked]>
Date: Fri, 19 Sep 2014 16:54:12 +1000

On Thu, Sep 18, 2014 at 06:26:50PM +1000, Michael Neuling wrote:
>From: Ian Munsie <[email-masked]>
>
>Some of the MSI IRQ code in pnv_pci_ioda_msi_setup() is generically useful so
>split it out.
>
>This will be used by some of the cxl PCIe code later.
>
>Signed-off-by: Ian Munsie <[email-masked]>
>Signed-off-by: Michael Neuling <[email-masked]>
>---
> arch/powerpc/platforms/powernv/pci-ioda.c | 43 ++++++++++++++++++-------------
> 1 file changed, 25 insertions(+), 18 deletions(-)
>
>diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
>index df241b1..194f90a 100644
>--- a/arch/powerpc/platforms/powernv/pci-ioda.c
>+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
>@@ -1306,14 +1306,36 @@ static void pnv_ioda2_msi_eoi(struct irq_data *d)
> 	icp_native_eoi(d);
> }
> 
>+
>+static void set_msi_irq_chip(struct pnv_phb *phb, unsigned int virq)
>+{
>+	struct irq_data *idata;
>+	struct irq_chip *ichip;
>+
>+	/*
>+	 * Change the IRQ chip for the MSI interrupts on PHB3.
>+	 * The corresponding IRQ chip should be populated for
>+	 * the first time.
>+	 */
>+	if (phb->type == PNV_PHB_IODA2) {
>+		if (!phb->ioda.irq_chip_init) {
>+			idata = irq_get_irq_data(virq);
>+			ichip = irq_data_get_irq_chip(idata);
>+			phb->ioda.irq_chip_init = 1;
>+			phb->ioda.irq_chip = *ichip;
>+			phb->ioda.irq_chip.irq_eoi = pnv_ioda2_msi_eoi;
>+		}
>+
>+		irq_set_chip(virq, &phb->ioda.irq_chip);
>+	}
>+}
>+

Nitpick: to check PHB type and bail early could avoid nested code :)

	if (phb->type != PNV_PHB_IODA2)
		return;

> static int pnv_pci_ioda_msi_setup(struct pnv_phb *phb, struct pci_dev *dev,
> 				  unsigned int hwirq, unsigned int virq,
> 				  unsigned int is_64, struct msi_msg *msg)
> {
> 	struct pnv_ioda_pe *pe = pnv_ioda_get_pe(dev);
> 	struct pci_dn *pdn = pci_get_pdn(dev);
>-	struct irq_data *idata;
>-	struct irq_chip *ichip;
> 	unsigned int xive_num = hwirq - phb->msi_base;
> 	__be32 data;
> 	int rc;
>@@ -1365,22 +1387,7 @@ static int pnv_pci_ioda_msi_setup(struct pnv_phb *phb, struct pci_dev *dev,
> 	}
> 	msg->data = be32_to_cpu(data);
> 
>-	/*
>-	 * Change the IRQ chip for the MSI interrupts on PHB3.
>-	 * The corresponding IRQ chip should be populated for
>-	 * the first time.
>-	 */
>-	if (phb->type == PNV_PHB_IODA2) {
>-		if (!phb->ioda.irq_chip_init) {
>-			idata = irq_get_irq_data(virq);
>-			ichip = irq_data_get_irq_chip(idata);
>-			phb->ioda.irq_chip_init = 1;
>-			phb->ioda.irq_chip = *ichip;
>-			phb->ioda.irq_chip.irq_eoi = pnv_ioda2_msi_eoi;
>-		}
>-
>-		irq_set_chip(virq, &phb->ioda.irq_chip);
>-	}
>+	set_msi_irq_chip(phb, virq);
> 
> 	pr_devel("%s: %s-bit MSI on hwirq %x (xive #%d),"
> 		 " address=%x_%08x data=%x PE# %d\n",

Thanks,
Gavin